Potential Renewable Energy Generation in Hong Kong, China

Prof. YANG Hongxing

15-05-2018

Outlines

The feed-in tariff introduced recently

Current development of solar and wind power generations in

China and the world

Potential solar PV power generation in Hong Kong, China

Potential offshore wind power generation in Hong Kong, China

Other potential renewable energy resources in HK, China

Conclusions

New development of RE in Hong Kong, China

Feed-in tariff rates announced on April 17, 2018

The rates: HK$3-5/kWh for solar and wind systems with a guaranteed rebate period of 15 years.

The rate level will help drastically reduce the payback period of most renewable energy systems to about 10 years and in turn motivate more people and organisations to install the system.

Power companies will also sell Renewable Energy Certificates. Revenue from certificate sales will be used to alleviate the impact of the Feed-in Tariff's introduction.

The majority would be able to accept around 5% increase in the tariff, or even some would support a 10% increase.

Details of the FiT

Capacity of the Renewable Energy System

FiT rate(per unit of electricity -kWh)

≤ 10 kW HK$ 5

> 10 kW - ≤ 200 kW HK$ 4

> 200 kW - ≤ 1MW HK$ 3

Three types of FiT rates will be offered according to the generation capacity of your RE system:

The rates listed above are effective from 1 Oct 2018 onwards and will be reviewed regularly.

China installed 52.8GW in 2017, a 53% increase over the prior year. China had installed 34.54GW in 2016 and reiterated that it was the clear market leader once again.

Source: Solar Power Europe 2018

Global Solar PV Installations

Forecast of energy structure in the world

The Forecast of Energy Demandand the Transformation of EnergyStructure (2000-2100):

Data source: Joint Research Centre

Solar PV may become the main power in 2100!

Rapid development of PV power generation

Potential BIPV in Hong Kong, China

Advantages of BIPV • No land use;• BIPV provides electricity at the point of use;• The PV elements become an integral part of

the building and reduce building material use;• Power is generated on site;• Cooling load can be reduced;• Renewable for low-carbon emission

buildings.

EMSD HQ in Hong Kong, China

PolyU in 1999

Lamma Power Plant

CLP Power’s Renewable Energy Generation System at Town Island

A standalone renewable energy (RE) generation system: 180kW solar panels and 2 nos. of 6kW wind turbines

Other PV Projects Year Venue Capacity (kW)

2016 Photovoltaic System at the Siu Ho Wan Sewage Treatment Works

1100

2016 Redevelopment of Tai Lam Centre forWomen

63

2016 Reprovisioning of Yaumatei SpecialistClinic at Queen Elizabeth Hospital

69

2016 Sports centre, community hall anddistrict library in Area 14B, Sha Tin

57

2016 Public library and indoor recreationcentre in Area 3, Yuen Long

23

2016 Reprovisioning of Yau Ma Tei PoliceStation

48

2015 Po Leung Kuk Stanley Ho Sau NanPrimary School

6

2015 West Kowloon Law Courts Building 462015 Redevelopment of Fire Services

TrainingSchool98

2015 Redevelopment of Victoria ParkSwimming Pool Complex

468

2015 Construction of Trade and IndustryTower in Kai Tak Development Area

46

BIPV potential study in Europe

Development potential of rooftop PV systems

Solar-Architectural Rules of thumb was used to estimate the PV-suitable rooftop area with the buildings’ ground floor area.

The procedure to estimate the potential PV-suitable rooftop area

Ground floor area 117 km2

Ratio “gross roof area / ground floor area ”

1.2

Gross roof area 140 km2

Architectural suitability factor

0.7

Architecturallysuitable roof area

98 km2

Solar suitability factor 0.55

The potential PV-suitable rooftop area

54 km2

PV-suitable rooftop area & optimal installation

The optimum orientation for PV installation in Hong Kong, China is facing south with tilted angle 15-23 for maximum accumulated annual power generation.

Rooftop installation potential & PV output

The potential total active rooftop area of PV modules was calculated as 37.4km2. The total potential installation capacity is estimated as 5.97 GWp.

The potential PV electricity output is about 5,981GWh,accounting for 14.2% of the total electricity use in 2011.Reduce the imports of coal and natural gas by 25% and 54% respectively and mitigate about 3 million tons of GHG emissions yearly.

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Our research in BIPV in PolyU

Study of the overall energy performance of BIPV facade:

real-time power generation performance thermal performance natural lighting performance

Power generation from ventilated BIPV

The monthly power generation of this ventilated BIPV system is about 4.5 kWh/m2 in last winter in Hong Kong, China.Using high efficiency see-through PV modules, such as CdTe and CIGS, could double the monthly power generation.

Study on semi-transparent solar PV windows

- Collaborative project with HA

PV systems Solar cell types Rated power Efficiency/

Transmittance

PV window 1 Semi-transparent a-

Si

a-Si: 56W*3 6.3%/20%

PV window 2 Semi-transparent

hollow a-Si

97W 6.8%/20%

PV shading 1 Poly-Si 260W 16%/opaque

PV shading 2 CIGS 150W 12%/opaque

N il d P l Si 260W 16%/

Study on semi-transparent solar PV windows - Characteristics of PV modules

Study on semi-transparent solar PV windows - Data acquisition system

Efficiency: 6.3%Transmittance: 20%Rated power: 63W/m2

Efficiency: 6.8%Transmittance: 20%Rated power: 68W/m2

Ventilated PV window

Hollow PV window

Study on semi-transparent solar PV windows

- Inside views of PV windows

Appropriate subsidies for BIPV

Appropriate subsidies and preferential feed-in tariff should be provided to increase users' enthusiasm for installing PV systems;

Common policy instruments:o Feed-in-tariffs (FIT)o Investment tax credits o Favorable financing schemeso Mandatory access and

purchase o One-time initial cost subsidy

Mainland Earlier SubsidiesZhejiang 0.52RMB/kWh

Anhui 2.67RMB/kWhJiangxi 4.42RMB/kWh (phase I)

3.42RMB/kWh (phase II)Shanghai 0.67RMB/kWh

Shandong 1.2RMB/kWh

Wind Power for power supply in urban area

- Most big cities locate along coastline areas;

- Offshore wind farms are veryclose to big cities;

- Wind power application increases fast in the world.

Developing Status of Wind Energy2016 was a record year for the wind industry as it was the third consecutive year that annualinstallations crossed 50GW. The new global total for wind power at the end of 2016 was 486.7GW, representing cumulative market growth of more than 12.6%.

By the end of last year the number of countries with more than 10,000 MW installed capacitywas 9: including 4 in Europe (Germany, Spain, UK and France); 2 in Asia-Pacific (China &India); 2 in North America (US & Canada) and 1 in Latin America (Brazil).

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Developing Status of Offshore Wind Energy

Global Cumulative Offshore Wind Capacity in 2016

2016 was also a typical year for offshore wind installations. New capacity additions totalednearly 2.2GW across five markets globally. This brought total offshore wind installed capacityto over 14.4 GW.

Annual installations of wind power in the EU have increased over the last 15 years from 3.2GW in 2000 to 14.4 GW in 2016. The total offshore wind capacity is still limited, but growthrates are pretty high.

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Wind power in Hong Kong, ChinaEnergy state in Hong Kong, China

Wind energy develops rapidly in the world, but renewable energies contribute only 0.6% of total energy demand in Hong Kong, China.

Abundant offshore wind energy resource in the territory.

Two offshore wind farms have been proposed by CLP and HKE which are the initial attempts in offshore wind development.

[1] Gao, X., H. Yang, and L. Lu, Study on offshore wind power potential and wind farm optimization in Hong Kong. Applied Energy, 2014. 130: p. 519-531.

[2] Gao, X., H. Yang, and L. Lu, Investigation into the optimal wind turbine layout patterns for a Hong Kong offshore wind farm. Energy, 2014. 73(0): p. 430-442.

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Wake Effect and Wave Interactions in a Wind Farm

Due to the wake effect, the layout of a wind farm physically limits the upper boundaryof its power generation potential. If not consider the wake effect properly, it will inducethe waste of investment and components’ redundancy.

In a wind farm, wind turbines not only generate energy but also induce wakes behindtheir swept areas.

Our research effort in wind power

7

Our research in wind power:- A new 2D wake model

Jenson: Jenson-Gaussian:

Three assumptions:

1. The same radius:

2. When r=rx :

3. The same mass flux:

Our research in wind powerA new 3D wake model

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results comparisons of the measurement data18

Field experiment

CWEX-13 Field Experiment:.

300 MW of GE 1.5 XLE (80m hub height, 80m D)

Three profiling lidars (WindCUBEv1)• WS and WD at 1 Hz; 40m to 220m above the surface; 29 June – 5 Sept, 2013

One scanning lidar (WindCUBE 200S)• Line-of-sight (LOS) velocities from six elevations of PPI scans

Turbine wake model development

Improved Jenson-Gaussian Wake Model: ValidationWith previous models and data from field experiment (Taylor’s study of Nibe site).Two turbines, 45m hub height , 40 diameters, wind speed of 8.55m/s.

.

‘Qualified’ good performance is obtained by the improved Jenson-Gaussian wake model !

Field experiment & findings

Validation for the Multiple Wakes of Turbines in RowFitting and Validation

.

Velocity deficit:

Wake width:

Results and Discussion of the MPGA optimization program.

Case (b): Constant Wind Speed of 12m/s with Variable Wind Directions

Turbine layout optimization program development

Hong Kong, China offshore wind power potential assessment.

Wind turbine:

5 MW wind turbine is selected.

Power generation:

Hong Kong, China offshore wind power potential assessment

Input Data Source for the Selected Offshore Wind Farms:.

Wind in the offshore wind farm near Lamma Island

One year’s wind data measured by The Hongkong Electric Co., Ltd. (HK Electric) has been used for the wind power potential analysis.

Hong Kong, China offshore wind power potential assessment.

Objective function: Lowest COECost factor calculations:

COE calculations:

Hong Kong, China offshore wind power potential assessment

Optimization results of the selected wind farm near Lamma Island and the assessment of Hong Kong, China offshore wind power potential

.

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Determination of the optimal layout patterns

Offshore wind power potential assessment.• The sea water area in Hong Kong, China is 1650.64 km2 which occupies 59.91%

of the Hong Kong, China territory area (2755.03 km2) .• The total sea water surface area and 3 km beyond Hong Kong, China that can be

used for offshore wind farms is 64 km2. • Our optimization study about wind turbine locations can increase power generation

of 13.94%.• The total potential power generation is then 6409 GWh (15.3% of the 2010 power

demand: 41869 GWh ).

• CO2 emission can be reduced by 51.26 108 kg.

Biogas production in sewage treatment works (STWs)

Landfill gas production and utilization

Incineration for power generation

Food waste for biogas production

Waste oil for biodiesel

Other renewable energy resources in Hong Kong, China

Biogas production in STWs

Sewage treatment procedures and biogas production

Biogasyield

2016 30010 280 393,000

Sewage treatment works in HK

Annual biogas production at four sewage treatment works in 2013:

The overall biogas production in 2013 was about 9.4 million m3. The equivalent electricity saved was more than 14 million kWh, which is equivalent to the annual electricity consumption of 1,560 four-member families.

Biogas production in STWs

Biogas utilization in STWs:Combined heat and power (CHP)

Figure: CHP system flow diagram in STWs Figure: Timeline of CHP installation in STWs

The total capacity of CHP in 2014 reached 3,650kW

The hot water produced can be used to improve the slurry temperature, thus to increase biogas production rate.

Landfill gas in HK

313

: 61 240

140 3,500

3,100 (2014 )

: 100 135

100 4,300

4,500 (2014 )

: 110170

120 6,100

7,300 (2014 )

Biogas from landfill gas in Hong Kong, China

Food waste recycling in HK

Approximately 3,640 tonnes food wasteproduced in Hong Kong, China every day.

OWTFs will adopt biological technologies to turn organic waste into compost and biogas for recovery.

Organic Waste Treatment Facilities (OWTF)

Three OWTFs are under construction.

More OWTFs are under planning by The Environmental Protection Department (EPD) .

Organic Waste Treatment Facilities Phase 1 at Siu Ho Wan 1 ,

Plant commissioning in 2017:200 tonnes of food waste per day;Surplus electricity of 14 million kWh/year,

adequate for use by 3,000 households 7,000 tonnes compost products per year for

beneficial uses Greenhouse gas reduction: 25,000 per annum Reduce disposal to landfills (73,000 t per

year)Organic Waste Treatment Facilities Phase 2 at Sha Ling

2 ,

Under construction:

300 tonnes of food waste per day;

Waste oil for biodiesel ASB Biodiesel HK (ASB ),

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Funding approval from LegCo was obtained on 9 January 2015. It is expected to commission in 2023.

Conclusions.

Both the local solar energy and offshore wind energy resources are very good for power generation. With the introduction of the FiT policy, there will be a fast development of BIPV soon in Hong Kong, China. Rooftop PV systems could provide 5,981GWh solar power annually, accounting for 14.2% of the total electricity demand in 2011. The annual wind energy generation could be 6409 GWh, accounting for 15.3% of the annual electricity demand in 2010.

A new turbine wake model and an optimal wind turbine layout have been proposed, which can provide the basic calculations for wind farms’ planning.

Incineration of solid waste for power generation represents the futuredevelopment for solid waste treatment.